The women's 400 metres event at the 2016 Summer Olympics took place between 13–15 August at the Olympic Stadium.

Summary Shaunae Miller of Bahamas was the world leading runner for 2016, followed by 2015 World Champion Allyson Felix. 2012 Olympic champion Sanya Richards-Ross had failed to make the American team due to a hamstring injury during the American trials.Landells, Steve (10 August 2016). Preview: women's 400m – Rio 2016 Olympic Games. IAAF. Retrieved on 14 August 2016.Senior outdoor 2016 400 Metres women. IAAF. Retrieved on 14 August 2016.

In qualifying, 2 athletes ran under 51 seconds, American Phyllis Francis and Oluwakemi Adekoya, who ran a Bahraini record. Another Nigerian born Bahraini, 18-year-old Salwa Eid Naser, won her heat in a personal best.Landells, Steve (13 August 2016). Report: women's 400m heats – Rio 2016 Olympic Games. IAAF. Retrieved on 14 August 2016.

In the final, Natasha Hastings made up most of the stagger on one of the favorites, Shaunae Miller and held the lead to the halfway point. Miller made up the stagger on Stephenie Ann McPherson in lane 8 to her outside. Starting about 150 metres into the race, Miller accelerated, passing Hastings before the halfway point in the far turn. In lane 4, Allyson Felix ran an even pace which saw her separate from the athletes inside of her and catching Shericka Jackson late in the second turn. Coming off the turn, Miller held a clear 2 metre advantage over Hastings, with Felix gaining on Hastings and Jackson more than a metre behind Felix. Hastings was passed by Felix who continued to gain on Miller. In the last few metres as Felix gained on her, Miller started to lean forward trying to get to the finish line. As Felix looked to pass her in the final step, Miller made a last desperate headlong dive across the line. The photo finish revealed her shoulders had crossed the line seven hundredths of a second ahead of Felix. Jamaican Shericka Jackson finished 3 metres back for bronze.

Felix's silver became her seventh Olympic medal. She would later earn two more Olympic gold medals as part of the winning 4x100 meters and 4x400 meters teams, tying her with Merlene Ottey as the most decorated woman in track and field history, with nine Olympic medals.

Records Prior to this competition, the existing global and area records were as follows:

Area Time (s) Athlete Nation Africa 49.10 Falilat Ogunkoya Asia 49.81 Ma Yuqin Europe 47.60 Marita Koch North, Central America and Caribbean 48.70 Sanya Richards Oceania 48.63 Cathy Freeman South America 49.64 Ximena Restrepo

Schedule All times are Brasilia Time (UTC-3) Date Time RoundSaturday, 13 August 2016 11:00Round 1Sunday, 14 August 2016 20:35SemifinalsMonday, 15 August 2016 22:45Finals

Results Heats Qualification rule: First 2 in each heat (Q) and the next 8 fastest (q) advance to the Semifinals

Heat 1 Rank Athlete Nation Time Notes 1 Stephenie Ann McPherson 51.36 2 Patience Okon George 51.83 3 Anneliese Rubie 51.92 , 4 Yuliya Olishevska 52.45 5 Djénébou Danté 52.85 6 Nirmala Sheoran 53.03 7 Gunta Latiševa-Čudare 53.08

Heat 2 Rank Athlete Nation Time Notes 1 Allyson Felix 51.24 2 Olha Zemlyak 51.40 3 Tamara Salaški 52.70 4 Tsholofelo Thipe 52.80 5 Iveta Putálová 52.82 6 Aauri Bokesa 53.51 7 Seren Bundy-Davies 53.63

Heat 3 Rank Athlete Nation Time Notes 1 Phyllis Francis 50.58 2 Kemi Adekoya 50.72 3 Margaret Bamgbose 51.43 4 Patrycja Wyciszkiewicz 52.02 , 5 Alicia Brown 52.27 6 Jailma de Lima 52.65 7 Justine Palframan 53.96

Heat 4 Rank Athlete Nation Time Notes 1 Natasha Hastings 51.31 2 Christine Ohuruogu 51.40 3 Maria Benedicta Chigbolu 52.06 4 Lydia Jele 52.24 5 Olha Bibik 52.33 6 Kendra Clarke 53.61 7 Vijona Kryeziu 54.30

Heat 5 Rank Athlete Nation Time Notes 1 Shaunae Miller 51.16 2 Morgan Mitchell 51.30 3 Ruth Spelmeyer 51.43 , 4 Emily Diamond 51.76 5 Kanika Beckles 52.41 6 Bianca Răzor 52.42 7 Kineke Alexander 52.45

Heat 6 Rank Athlete Nation Time Notes 1 Salwa Eid Naser 51.06 , 2 Libania Grenot 51.17 3 Floria Gueï 51.29 4 Cátia Azevedo 52.38 5 Mariam Kromah 52.79 6 Nguyễn Thị Huyền 52.97 7 Irini Vasiliou 54.37 8 Maryan Nuh Muse 1:10.14

Heat 7 Rank Athlete Nation Time Notes 1 Shericka Jackson 51.73 2 Kabange Mupopo 51.76 3 Justyna Święty 51.82 4 Christine Botlogetswe 52.37 5 Omolara Omotosho 53.22 6 Elina Mikhina 53.83 7 Dalal Mesfer Al-Harith 1:07.12

Heat 8 Rank Athlete Nation Time Notes 1 Christine Day 51.54 2 Carline Muir 51.57 3 Małgorzata Hołub 51.80 4 Geisa Coutinho 52.05 5 Aliyah Abrams 52.79 6 Mariama Mamoudou Ittatou 54.32 DQ (7) Anastassya Kudinova 56.03 DQ (Doping)

Semifinals Semifinal 1 Rank Lane Athlete Nation Reaction Time Notes 1 6 Phyllis Francis 0.189 50.31 2 5 Stephenie Ann McPherson 0.158 50.69 3 4 Olha Zemlyak 0.189 50.75 , 4 3 Kemi Adekoya 0.161 50.88 5 7 Christine Ohuruogu 0.145 51.22 6 2 Ruth Spelmeyer 0.155 51.61 7 8 Margaret Bamgbose 0.212 51.92 8 1 Patrycja Wyciszkiewicz 0.174 52.51

Semifinal 2 Rank Lane Athlete Nation Reaction Time Notes 1 6 Shericka Jackson 0.184 49.83 , 2 5 Natasha Hastings 0.188 49.90 , 3 3 Salwa Eid Naser 0.139 50.88 4 8 Floria Gueï 0.178 51.08 5 7 Carline Muir 0.226 51.11 6 1 Emily Diamond 0.178 51.49 7 2 Małgorzata Hołub 0.136 51.93 8 4 Morgan Mitchell 0.136 52.68

Semifinal 3 Rank Lane Athlete Nation Reaction Time Notes 1 3 Allyson Felix 0.174 49.67 , 2 4 Shaunae Miller 0.167 49.91 3 6 Libania Grenot 0.156 50.60 4 5 Christine Day 0.186 51.53 5 1 Justyna Święty 0.171 51.62 6 2 Anneliese Rubie 0.172 51.96 7 8 Kabange Mupopo 0.155 52.04 8 7 Patience Okon George 0.161 52.52

Final Rank Lane Athlete Nation Reaction Time Notes 7 Shaunae Miller 0.155 49.44 4 Allyson Felix 0.177 49.51 5 Shericka Jackson 0.176 49.85 4 6 Natasha Hastings 0.161 50.34 5 3 Phyllis Francis 0.219 50.41 6 8 Stephenie Ann McPherson 0.133 50.97 7 2 Libania Grenot 0.149 51.25 DSQ 1 Olha Zemlyak 0.183 51.24

References